includes/specialpage/SpecialPageFactory.php

   1 <?php
   2 /**
   3  * Factory for handling the special page list and generating SpecialPage objects.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup SpecialPage
  22  * @defgroup SpecialPage SpecialPage
  23  */
  24 use MediaWiki\Linker\LinkRenderer;
  25 use Wikimedia\ObjectFactory;
  26
  27 /**
  28  * Factory for handling the special page list and generating SpecialPage objects.
  29  *
  30  * To add a special page in an extension, add to $wgSpecialPages either
  31  * an object instance or an array containing the name and constructor
  32  * parameters. The latter is preferred for performance reasons.
  33  *
  34  * The object instantiated must be either an instance of SpecialPage or a
  35  * sub-class thereof. It must have an execute() method, which sends the HTML
  36  * for the special page to $wgOut. The parent class has an execute() method
  37  * which distributes the call to the historical global functions. Additionally,
  38  * execute() also checks if the user has the necessary access privileges
  39  * and bails out if not.
  40  *
  41  * To add a core special page, use the similar static list in
  42  * SpecialPageFactory::$list. To remove a core static special page at runtime, use
  43  * a SpecialPage_initList hook.
  44  *
  45  * @ingroup SpecialPage
  46  * @since 1.17
  47  */
  48 class SpecialPageFactory {
  49         /**
  50          * List of special page names to the subclass of SpecialPage which handles them.
  51          */
  52         private static $coreList = [
  53                 // Maintenance Reports
  54                 'BrokenRedirects' => BrokenRedirectsPage::class,
  55                 'Deadendpages' => DeadendPagesPage::class,
  56                 'DoubleRedirects' => DoubleRedirectsPage::class,
  57                 'Longpages' => LongPagesPage::class,
  58                 'Ancientpages' => AncientPagesPage::class,
  59                 'Lonelypages' => LonelyPagesPage::class,
  60                 'Fewestrevisions' => FewestrevisionsPage::class,
  61                 'Withoutinterwiki' => WithoutInterwikiPage::class,
  62                 'Protectedpages' => SpecialProtectedpages::class,
  63                 'Protectedtitles' => SpecialProtectedtitles::class,
  64                 'Shortpages' => ShortPagesPage::class,
  65                 'Uncategorizedcategories' => UncategorizedCategoriesPage::class,
  66                 'Uncategorizedimages' => UncategorizedImagesPage::class,
  67                 'Uncategorizedpages' => UncategorizedPagesPage::class,
  68                 'Uncategorizedtemplates' => UncategorizedTemplatesPage::class,
  69                 'Unusedcategories' => UnusedCategoriesPage::class,
  70                 'Unusedimages' => UnusedimagesPage::class,
  71                 'Unusedtemplates' => UnusedtemplatesPage::class,
  72                 'Unwatchedpages' => UnwatchedpagesPage::class,
  73                 'Wantedcategories' => WantedCategoriesPage::class,
  74                 'Wantedfiles' => WantedFilesPage::class,
  75                 'Wantedpages' => WantedPagesPage::class,
  76                 'Wantedtemplates' => WantedTemplatesPage::class,
  77
  78                 // List of pages
  79                 'Allpages' => SpecialAllPages::class,
  80                 'Prefixindex' => SpecialPrefixindex::class,
  81                 'Categories' => SpecialCategories::class,
  82                 'Listredirects' => ListredirectsPage::class,
  83                 'PagesWithProp' => SpecialPagesWithProp::class,
  84                 'TrackingCategories' => SpecialTrackingCategories::class,
  85
  86                 // Authentication
  87                 'Userlogin' => SpecialUserLogin::class,
  88                 'Userlogout' => SpecialUserLogout::class,
  89                 'CreateAccount' => SpecialCreateAccount::class,
  90                 'LinkAccounts' => SpecialLinkAccounts::class,
  91                 'UnlinkAccounts' => SpecialUnlinkAccounts::class,
  92                 'ChangeCredentials' => SpecialChangeCredentials::class,
  93                 'RemoveCredentials' => SpecialRemoveCredentials::class,
  94
  95                 // Users and rights
  96                 'Activeusers' => SpecialActiveUsers::class,
  97                 'Block' => SpecialBlock::class,
  98                 'Unblock' => SpecialUnblock::class,
  99                 'BlockList' => SpecialBlockList::class,
 100                 'AutoblockList' => SpecialAutoblockList::class,
 101                 'ChangePassword' => SpecialChangePassword::class,
 102                 'BotPasswords' => SpecialBotPasswords::class,
 103                 'PasswordReset' => SpecialPasswordReset::class,
 104                 'DeletedContributions' => DeletedContributionsPage::class,
 105                 'Preferences' => SpecialPreferences::class,
 106                 'ResetTokens' => SpecialResetTokens::class,
 107                 'Contributions' => SpecialContributions::class,
 108                 'Listgrouprights' => SpecialListGroupRights::class,
 109                 'Listgrants' => SpecialListGrants::class,
 110                 'Listusers' => SpecialListUsers::class,
 111                 'Listadmins' => SpecialListAdmins::class,
 112                 'Listbots' => SpecialListBots::class,
 113                 'Userrights' => UserrightsPage::class,
 114                 'EditWatchlist' => SpecialEditWatchlist::class,
 115
 116                 // Recent changes and logs
 117                 'Newimages' => SpecialNewFiles::class,
 118                 'Log' => SpecialLog::class,
 119                 'Watchlist' => SpecialWatchlist::class,
 120                 'Newpages' => SpecialNewpages::class,
 121                 'Recentchanges' => SpecialRecentChanges::class,
 122                 'Recentchangeslinked' => SpecialRecentChangesLinked::class,
 123                 'Tags' => SpecialTags::class,
 124
 125                 // Media reports and uploads
 126                 'Listfiles' => SpecialListFiles::class,
 127                 'Filepath' => SpecialFilepath::class,
 128                 'MediaStatistics' => MediaStatisticsPage::class,
 129                 'MIMEsearch' => MIMEsearchPage::class,
 130                 'FileDuplicateSearch' => FileDuplicateSearchPage::class,
 131                 'Upload' => SpecialUpload::class,
 132                 'UploadStash' => SpecialUploadStash::class,
 133                 'ListDuplicatedFiles' => ListDuplicatedFilesPage::class,
 134
 135                 // Data and tools
 136                 'ApiSandbox' => SpecialApiSandbox::class,
 137                 'Statistics' => SpecialStatistics::class,
 138                 'Allmessages' => SpecialAllMessages::class,
 139                 'Version' => SpecialVersion::class,
 140                 'Lockdb' => SpecialLockdb::class,
 141                 'Unlockdb' => SpecialUnlockdb::class,
 142
 143                 // Redirecting special pages
 144                 'LinkSearch' => LinkSearchPage::class,
 145                 'Randompage' => RandomPage::class,
 146                 'RandomInCategory' => SpecialRandomInCategory::class,
 147                 'Randomredirect' => SpecialRandomredirect::class,
 148                 'Randomrootpage' => SpecialRandomrootpage::class,
 149                 'GoToInterwiki' => SpecialGoToInterwiki::class,
 150
 151                 // High use pages
 152                 'Mostlinkedcategories' => MostlinkedCategoriesPage::class,
 153                 'Mostimages' => MostimagesPage::class,
 154                 'Mostinterwikis' => MostinterwikisPage::class,
 155                 'Mostlinked' => MostlinkedPage::class,
 156                 'Mostlinkedtemplates' => MostlinkedTemplatesPage::class,
 157                 'Mostcategories' => MostcategoriesPage::class,
 158                 'Mostrevisions' => MostrevisionsPage::class,
 159
 160                 // Page tools
 161                 'ComparePages' => SpecialComparePages::class,
 162                 'Export' => SpecialExport::class,
 163                 'Import' => SpecialImport::class,
 164                 'Undelete' => SpecialUndelete::class,
 165                 'Whatlinkshere' => SpecialWhatLinksHere::class,
 166                 'MergeHistory' => SpecialMergeHistory::class,
 167                 'ExpandTemplates' => SpecialExpandTemplates::class,
 168
 169                 // Other
 170                 'Booksources' => SpecialBookSources::class,
 171
 172                 // Unlisted / redirects
 173                 'ApiHelp' => SpecialApiHelp::class,
 174                 'Blankpage' => SpecialBlankpage::class,
 175                 'Diff' => SpecialDiff::class,
 176                 'EditTags' => SpecialEditTags::class,
 177                 'Emailuser' => SpecialEmailUser::class,
 178                 'Movepage' => MovePageForm::class,
 179                 'Mycontributions' => SpecialMycontributions::class,
 180                 'MyLanguage' => SpecialMyLanguage::class,
 181                 'Mypage' => SpecialMypage::class,
 182                 'Mytalk' => SpecialMytalk::class,
 183                 'Myuploads' => SpecialMyuploads::class,
 184                 'AllMyUploads' => SpecialAllMyUploads::class,
 185                 'PermanentLink' => SpecialPermanentLink::class,
 186                 'Redirect' => SpecialRedirect::class,
 187                 'Revisiondelete' => SpecialRevisionDelete::class,
 188                 'RunJobs' => SpecialRunJobs::class,
 189                 'Specialpages' => SpecialSpecialpages::class,
 190                 'PageData' => SpecialPageData::class,
 191         ];
 192
 193         private static $list;
 194         private static $aliases;
 195
 196         /**
 197          * Reset the internal list of special pages. Useful when changing $wgSpecialPages after
 198          * the internal list has already been initialized, e.g. during testing.
 199          */
 200         public static function resetList() {
 201                 self::$list = null;
 202                 self::$aliases = null;
 203         }
 204
 205         /**
 206          * Returns a list of canonical special page names.
 207          * May be used to iterate over all registered special pages.
 208          *
 209          * @return string[]
 210          */
 211         public static function getNames() {
 212                 return array_keys( self::getPageList() );
 213         }
 214
 215         /**
 216          * Get the special page list as an array
 217          *
 218          * @deprecated since 1.24, use getNames() instead.
 219          * @return array
 220          */
 221         public static function getList() {
 222                 wfDeprecated( __FUNCTION__, '1.24' );
 223                 return self::getPageList();
 224         }
 225
 226         /**
 227          * Get the special page list as an array
 228          *
 229          * @return array
 230          */
 231         private static function getPageList() {
 232                 global $wgSpecialPages;
 233                 global $wgDisableInternalSearch, $wgEmailAuthentication;
 234                 global $wgEnableEmail, $wgEnableJavaScriptTest;
 235                 global $wgPageLanguageUseDB, $wgContentHandlerUseDB;
 236
 237                 if ( !is_array( self::$list ) ) {
 238                         self::$list = self::$coreList;
 239
 240                         if ( !$wgDisableInternalSearch ) {
 241                                 self::$list['Search'] = SpecialSearch::class;
 242                         }
 243
 244                         if ( $wgEmailAuthentication ) {
 245                                 self::$list['Confirmemail'] = EmailConfirmation::class;
 246                                 self::$list['Invalidateemail'] = EmailInvalidation::class;
 247                         }
 248
 249                         if ( $wgEnableEmail ) {
 250                                 self::$list['ChangeEmail'] = SpecialChangeEmail::class;
 251                         }
 252
 253                         if ( $wgEnableJavaScriptTest ) {
 254                                 self::$list['JavaScriptTest'] = SpecialJavaScriptTest::class;
 255                         }
 256
 257                         if ( $wgPageLanguageUseDB ) {
 258                                 self::$list['PageLanguage'] = SpecialPageLanguage::class;
 259                         }
 260                         if ( $wgContentHandlerUseDB ) {
 261                                 self::$list['ChangeContentModel'] = SpecialChangeContentModel::class;
 262                         }
 263
 264                         // Add extension special pages
 265                         self::$list = array_merge( self::$list, $wgSpecialPages );
 266
 267                         // This hook can be used to disable unwanted core special pages
 268                         // or conditionally register special pages.
 269                         Hooks::run( 'SpecialPage_initList', [ &self::$list ] );
 270
 271                 }
 272
 273                 return self::$list;
 274         }
 275
 276         /**
 277          * Initialise and return the list of special page aliases. Returns an array where
 278          * the key is an alias, and the value is the canonical name of the special page.
 279          * All registered special pages are guaranteed to map to themselves.
 280          * @return array
 281          */
 282         private static function getAliasList() {
 283                 if ( is_null( self::$aliases ) ) {
 284                         global $wgContLang;
 285                         $aliases = $wgContLang->getSpecialPageAliases();
 286                         $pageList = self::getPageList();
 287
 288                         self::$aliases = [];
 289                         $keepAlias = [];
 290
 291                         // Force every canonical name to be an alias for itself.
 292                         foreach ( $pageList as $name => $stuff ) {
 293                                 $caseFoldedAlias = $wgContLang->caseFold( $name );
 294                                 self::$aliases[$caseFoldedAlias] = $name;
 295                                 $keepAlias[$caseFoldedAlias] = 'canonical';
 296                         }
 297
 298                         // Check for $aliases being an array since Language::getSpecialPageAliases can return null
 299                         if ( is_array( $aliases ) ) {
 300                                 foreach ( $aliases as $realName => $aliasList ) {
 301                                         $aliasList = array_values( $aliasList );
 302                                         foreach ( $aliasList as $i => $alias ) {
 303                                                 $caseFoldedAlias = $wgContLang->caseFold( $alias );
 304
 305                                                 if ( isset( self::$aliases[$caseFoldedAlias] ) &&
 306                                                         $realName === self::$aliases[$caseFoldedAlias]
 307                                                 ) {
 308                                                         // Ignore same-realName conflicts
 309                                                         continue;
 310                                                 }
 311
 312                                                 if ( !isset( $keepAlias[$caseFoldedAlias] ) ) {
 313                                                         self::$aliases[$caseFoldedAlias] = $realName;
 314                                                         if ( !$i ) {
 315                                                                 $keepAlias[$caseFoldedAlias] = 'first';
 316                                                         }
 317                                                 } elseif ( !$i ) {
 318                                                         wfWarn( "First alias '$alias' for $realName conflicts with " .
 319                                                                 "{$keepAlias[$caseFoldedAlias]} alias for " .
 320                                                                 self::$aliases[$caseFoldedAlias]
 321                                                         );
 322                                                 }
 323                                         }
 324                                 }
 325                         }
 326                 }
 327
 328                 return self::$aliases;
 329         }
 330
 331         /**
 332          * Given a special page name with a possible subpage, return an array
 333          * where the first element is the special page name and the second is the
 334          * subpage.
 335          *
 336          * @param string $alias
 337          * @return array Array( String, String|null ), or array( null, null ) if the page is invalid
 338          */
 339         public static function resolveAlias( $alias ) {
 340                 global $wgContLang;
 341                 $bits = explode( '/', $alias, 2 );
 342
 343                 $caseFoldedAlias = $wgContLang->caseFold( $bits[0] );
 344                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 345                 $aliases = self::getAliasList();
 346                 if ( isset( $aliases[$caseFoldedAlias] ) ) {
 347                         $name = $aliases[$caseFoldedAlias];
 348                 } else {
 349                         return [ null, null ];
 350                 }
 351
 352                 if ( !isset( $bits[1] ) ) { // T4087
 353                         $par = null;
 354                 } else {
 355                         $par = $bits[1];
 356                 }
 357
 358                 return [ $name, $par ];
 359         }
 360
 361         /**
 362          * Check if a given name exist as a special page or as a special page alias
 363          *
 364          * @param string $name Name of a special page
 365          * @return bool True if a special page exists with this name
 366          */
 367         public static function exists( $name ) {
 368                 list( $title, /*...*/ ) = self::resolveAlias( $name );
 369
 370                 $specialPageList = self::getPageList();
 371                 return isset( $specialPageList[$title] );
 372         }
 373
 374         /**
 375          * Find the object with a given name and return it (or NULL)
 376          *
 377          * @param string $name Special page name, may be localised and/or an alias
 378          * @return SpecialPage|null SpecialPage object or null if the page doesn't exist
 379          */
 380         public static function getPage( $name ) {
 381                 list( $realName, /*...*/ ) = self::resolveAlias( $name );
 382
 383                 $specialPageList = self::getPageList();
 384
 385                 if ( isset( $specialPageList[$realName] ) ) {
 386                         $rec = $specialPageList[$realName];
 387
 388                         if ( is_callable( $rec ) ) {
 389                                 // Use callback to instantiate the special page
 390                                 $page = call_user_func( $rec );
 391                         } elseif ( is_string( $rec ) ) {
 392                                 $className = $rec;
 393                                 $page = new $className;
 394                         } elseif ( is_array( $rec ) ) {
 395                                 $className = array_shift( $rec );
 396                                 // @deprecated, officially since 1.18, unofficially since forever
 397                                 wfDeprecated( "Array syntax for \$wgSpecialPages is deprecated ($className), " .
 398                                         "define a subclass of SpecialPage instead.", '1.18' );
 399                                 $page = ObjectFactory::getObjectFromSpec( [
 400                                         'class' => $className,
 401                                         'args' => $rec,
 402                                         'closure_expansion' => false,
 403                                 ] );
 404                         } elseif ( $rec instanceof SpecialPage ) {
 405                                 $page = $rec; // XXX: we should deep clone here
 406                         } else {
 407                                 $page = null;
 408                         }
 409
 410                         if ( $page instanceof SpecialPage ) {
 411                                 return $page;
 412                         } else {
 413                                 // It's not a classname, nor a callback, nor a legacy constructor array,
 414                                 // nor a special page object. Give up.
 415                                 wfLogWarning( "Cannot instantiate special page $realName: bad spec!" );
 416                                 return null;
 417                         }
 418
 419                 } else {
 420                         return null;
 421                 }
 422         }
 423
 424         /**
 425          * Return categorised listable special pages which are available
 426          * for the current user, and everyone.
 427          *
 428          * @param User $user User object to check permissions, $wgUser will be used
 429          *        if not provided
 430          * @return array ( string => Specialpage )
 431          */
 432         public static function getUsablePages( User $user = null ) {
 433                 $pages = [];
 434                 if ( $user === null ) {
 435                         global $wgUser;
 436                         $user = $wgUser;
 437                 }
 438                 foreach ( self::getPageList() as $name => $rec ) {
 439                         $page = self::getPage( $name );
 440                         if ( $page ) { // not null
 441                                 $page->setContext( RequestContext::getMain() );
 442                                 if ( $page->isListed()
 443                                         && ( !$page->isRestricted() || $page->userCanExecute( $user ) )
 444                                 ) {
 445                                         $pages[$name] = $page;
 446                                 }
 447                         }
 448                 }
 449
 450                 return $pages;
 451         }
 452
 453         /**
 454          * Return categorised listable special pages for all users
 455          *
 456          * @return array ( string => Specialpage )
 457          */
 458         public static function getRegularPages() {
 459                 $pages = [];
 460                 foreach ( self::getPageList() as $name => $rec ) {
 461                         $page = self::getPage( $name );
 462                         if ( $page && $page->isListed() && !$page->isRestricted() ) {
 463                                 $pages[$name] = $page;
 464                         }
 465                 }
 466
 467                 return $pages;
 468         }
 469
 470         /**
 471          * Return categorised listable special pages which are available
 472          * for the current user, but not for everyone
 473          *
 474          * @param User|null $user User object to use or null for $wgUser
 475          * @return array ( string => Specialpage )
 476          */
 477         public static function getRestrictedPages( User $user = null ) {
 478                 $pages = [];
 479                 if ( $user === null ) {
 480                         global $wgUser;
 481                         $user = $wgUser;
 482                 }
 483                 foreach ( self::getPageList() as $name => $rec ) {
 484                         $page = self::getPage( $name );
 485                         if ( $page
 486                                 && $page->isListed()
 487                                 && $page->isRestricted()
 488                                 && $page->userCanExecute( $user )
 489                         ) {
 490                                 $pages[$name] = $page;
 491                         }
 492                 }
 493
 494                 return $pages;
 495         }
 496
 497         /**
 498          * Execute a special page path.
 499          * The path may contain parameters, e.g. Special:Name/Params
 500          * Extracts the special page name and call the execute method, passing the parameters
 501          *
 502          * Returns a title object if the page is redirected, false if there was no such special
 503          * page, and true if it was successful.
 504          *
 505          * @param Title &$title
 506          * @param IContextSource &$context
 507          * @param bool $including Bool output is being captured for use in {{special:whatever}}
 508          * @param LinkRenderer|null $linkRenderer (since 1.28)
 509          *
 510          * @return bool|Title
 511          */
 512         public static function executePath( Title &$title, IContextSource &$context, $including = false,
 513                 LinkRenderer $linkRenderer = null
 514         ) {
 515                 // @todo FIXME: Redirects broken due to this call
 516                 $bits = explode( '/', $title->getDBkey(), 2 );
 517                 $name = $bits[0];
 518                 if ( !isset( $bits[1] ) ) { // T4087
 519                         $par = null;
 520                 } else {
 521                         $par = $bits[1];
 522                 }
 523
 524                 $page = self::getPage( $name );
 525                 if ( !$page ) {
 526                         $context->getOutput()->setArticleRelated( false );
 527                         $context->getOutput()->setRobotPolicy( 'noindex,nofollow' );
 528
 529                         global $wgSend404Code;
 530                         if ( $wgSend404Code ) {
 531                                 $context->getOutput()->setStatusCode( 404 );
 532                         }
 533
 534                         $context->getOutput()->showErrorPage( 'nosuchspecialpage', 'nospecialpagetext' );
 535
 536                         return false;
 537                 }
 538
 539                 if ( !$including ) {
 540                         // Narrow DB query expectations for this HTTP request
 541                         $trxLimits = $context->getConfig()->get( 'TrxProfilerLimits' );
 542                         $trxProfiler = Profiler::instance()->getTransactionProfiler();
 543                         if ( $context->getRequest()->wasPosted() && !$page->doesWrites() ) {
 544                                 $trxProfiler->setExpectations( $trxLimits['POST-nonwrite'], __METHOD__ );
 545                                 $context->getRequest()->markAsSafeRequest();
 546                         }
 547                 }
 548
 549                 // Page exists, set the context
 550                 $page->setContext( $context );
 551
 552                 if ( !$including ) {
 553                         // Redirect to canonical alias for GET commands
 554                         // Not for POST, we'd lose the post data, so it's best to just distribute
 555                         // the request. Such POST requests are possible for old extensions that
 556                         // generate self-links without being aware that their default name has
 557                         // changed.
 558                         if ( $name != $page->getLocalName() && !$context->getRequest()->wasPosted() ) {
 559                                 $query = $context->getRequest()->getQueryValues();
 560                                 unset( $query['title'] );
 561                                 $title = $page->getPageTitle( $par );
 562                                 $url = $title->getFullURL( $query );
 563                                 $context->getOutput()->redirect( $url );
 564
 565                                 return $title;
 566                         } else {
 567                                 $context->setTitle( $page->getPageTitle( $par ) );
 568                         }
 569                 } elseif ( !$page->isIncludable() ) {
 570                         return false;
 571                 }
 572
 573                 $page->including( $including );
 574                 if ( $linkRenderer ) {
 575                         $page->setLinkRenderer( $linkRenderer );
 576                 }
 577
 578                 // Execute special page
 579                 $page->run( $par );
 580
 581                 return true;
 582         }
 583
 584         /**
 585          * Just like executePath() but will override global variables and execute
 586          * the page in "inclusion" mode. Returns true if the execution was
 587          * successful or false if there was no such special page, or a title object
 588          * if it was a redirect.
 589          *
 590          * Also saves the current $wgTitle, $wgOut, $wgRequest, $wgUser and $wgLang
 591          * variables so that the special page will get the context it'd expect on a
 592          * normal request, and then restores them to their previous values after.
 593          *
 594          * @param Title $title
 595          * @param IContextSource $context
 596          * @param LinkRenderer|null $linkRenderer (since 1.28)
 597          * @return string HTML fragment
 598          */
 599         public static function capturePath(
 600                 Title $title, IContextSource $context, LinkRenderer $linkRenderer = null
 601         ) {
 602                 global $wgTitle, $wgOut, $wgRequest, $wgUser, $wgLang;
 603                 $main = RequestContext::getMain();
 604
 605                 // Save current globals and main context
 606                 $glob = [
 607                         'title' => $wgTitle,
 608                         'output' => $wgOut,
 609                         'request' => $wgRequest,
 610                         'user' => $wgUser,
 611                         'language' => $wgLang,
 612                 ];
 613                 $ctx = [
 614                         'title' => $main->getTitle(),
 615                         'output' => $main->getOutput(),
 616                         'request' => $main->getRequest(),
 617                         'user' => $main->getUser(),
 618                         'language' => $main->getLanguage(),
 619                 ];
 620
 621                 // Override
 622                 $wgTitle = $title;
 623                 $wgOut = $context->getOutput();
 624                 $wgRequest = $context->getRequest();
 625                 $wgUser = $context->getUser();
 626                 $wgLang = $context->getLanguage();
 627                 $main->setTitle( $title );
 628                 $main->setOutput( $context->getOutput() );
 629                 $main->setRequest( $context->getRequest() );
 630                 $main->setUser( $context->getUser() );
 631                 $main->setLanguage( $context->getLanguage() );
 632
 633                 // The useful part
 634                 $ret = self::executePath( $title, $context, true, $linkRenderer );
 635
 636                 // Restore old globals and context
 637                 $wgTitle = $glob['title'];
 638                 $wgOut = $glob['output'];
 639                 $wgRequest = $glob['request'];
 640                 $wgUser = $glob['user'];
 641                 $wgLang = $glob['language'];
 642                 $main->setTitle( $ctx['title'] );
 643                 $main->setOutput( $ctx['output'] );
 644                 $main->setRequest( $ctx['request'] );
 645                 $main->setUser( $ctx['user'] );
 646                 $main->setLanguage( $ctx['language'] );
 647
 648                 return $ret;
 649         }
 650
 651         /**
 652          * Get the local name for a specified canonical name
 653          *
 654          * @param string $name
 655          * @param string|bool $subpage
 656          * @return string
 657          */
 658         public static function getLocalNameFor( $name, $subpage = false ) {
 659                 global $wgContLang;
 660                 $aliases = $wgContLang->getSpecialPageAliases();
 661                 $aliasList = self::getAliasList();
 662
 663                 // Find the first alias that maps back to $name
 664                 if ( isset( $aliases[$name] ) ) {
 665                         $found = false;
 666                         foreach ( $aliases[$name] as $alias ) {
 667                                 $caseFoldedAlias = $wgContLang->caseFold( $alias );
 668                                 $caseFoldedAlias = str_replace( ' ', '_', $caseFoldedAlias );
 669                                 if ( isset( $aliasList[$caseFoldedAlias] ) &&
 670                                         $aliasList[$caseFoldedAlias] === $name
 671                                 ) {
 672                                         $name = $alias;
 673                                         $found = true;
 674                                         break;
 675                                 }
 676                         }
 677                         if ( !$found ) {
 678                                 wfWarn( "Did not find a usable alias for special page '$name'. " .
 679                                         "It seems all defined aliases conflict?" );
 680                         }
 681                 } else {
 682                         // Check if someone misspelled the correct casing
 683                         if ( is_array( $aliases ) ) {
 684                                 foreach ( $aliases as $n => $values ) {
 685                                         if ( strcasecmp( $name, $n ) === 0 ) {
 686                                                 wfWarn( "Found alias defined for $n when searching for " .
 687                                                         "special page aliases for $name. Case mismatch?" );
 688                                                 return self::getLocalNameFor( $n, $subpage );
 689                                         }
 690                                 }
 691                         }
 692
 693                         wfWarn( "Did not find alias for special page '$name'. " .
 694                                 "Perhaps no aliases are defined for it?" );
 695                 }
 696
 697                 if ( $subpage !== false && !is_null( $subpage ) ) {
 698                         // Make sure it's in dbkey form
 699                         $subpage = str_replace( ' ', '_', $subpage );
 700                         $name = "$name/$subpage";
 701                 }
 702
 703                 return $wgContLang->ucfirst( $name );
 704         }
 705
 706         /**
 707          * Get a title for a given alias
 708          *
 709          * @param string $alias
 710          * @return Title|null Title or null if there is no such alias
 711          */
 712         public static function getTitleForAlias( $alias ) {
 713                 list( $name, $subpage ) = self::resolveAlias( $alias );
 714                 if ( $name != null ) {
 715                         return SpecialPage::getTitleFor( $name, $subpage );
 716                 } else {
 717                         return null;
 718                 }
 719         }
 720 }